1. Field of the Invention
Embodiments of the present invention generally relate to a method and apparatus for ex-situ cleaning of a chamber component. More particularly, embodiments of the present invention generally relate to a method and apparatus for ex-situ cleaning of a chamber component used in a semiconductor processing chamber.
2. Description of the Related Art
Plasma processing of semiconductor wafers in the manufacture of microelectronic integrated circuits is used in dielectric etching, metal etching, chemical vapor deposition and other processes. In semiconductor substrate processing, the trend towards increasingly smaller feature sizes and line-widths has placed a premium on the ability to mask, etch, and deposit material on a semiconductor substrate, with greater precision.
Typically, etching is accomplished by applying radio frequency (RF) power to a working gas supplied to a low pressure processing region over a substrate supported by a support member. The resulting electric field creates a reaction zone in the processing region that excites the working gas into a plasma. The support member is biased to attract ions within the plasma towards the substrate supported thereon. Ions migrate towards a boundary layer of the plasma adjacent to the substrate and accelerate upon leaving the boundary layer. The accelerated ions produce the energy required to remove, or etch, the material from the surface of the substrate. As the accelerated ions can etch other components within the processing chamber, it is important that the plasma be confined to the processing region above the substrate. The etch gas is typically directed through a showerhead situated near the top of the chamber. Fluorine-based chemistries are generally used during etching processes.
However, the use of fluorine, while advantageous for the etching process, reacts to form deposits in the narrow channels of the showerhead and on other surfaces that are made of aluminum, a material commonly used in etch chambers. The aluminum fluoride deposits formed in this manner have a generally rough surface topography. The rough surface of the aluminum fluoride deposits often blocks the channels of the showerhead. Additionally, the aluminum fluoride deposits within the gas channels become a source of particulate contamination. Current cleaning methods either fail to adequately clean the deposits on the showerhead or require significant system downtime, further resulting in increased overall production costs.
Therefore, there is a need for an improved apparatus and process for cleaning chamber components such as showerheads that provide significantly less downtime for chamber maintenance and cleaning.